The European Union condemned the attacks in a statement, saying they "highlight the importance of restoring peace and the rule of law throughout the country."

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Morning Q & A: Conflict in Yemen

Attacks come amid peace talks

The attack came on a day when the government resumed peace talks with the country's original rebels. Houthi militants, supported by Iran, overran the capital of Sanaa last year, forcing President Abedrabbo Mansour Hadi to flee to Saudi Arabia.

Hadi subsequently returned to establish a provisional capital in the port city of Aden.

Saudi Arabia lead an Arab coalition that began a bombing campaign in Yemen in March 2015. Their aim had been to oust Houthi rebels and pave the way for a return to power of President Hadi.

Despite a fierce, and at times indiscriminate, air campaign, the Houthi rebels could not be routed, forcing the two sides to the negotiating table. More than 6,400 people have been killed in the fighting, and 2.8 million have been displaced, according to the United Nations.

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What’s going on in Yemen?

The world body says 82 percent of Yemen's population is in need of aid.

With much of the country left ungoverned IS militants moved in to fill the vacuum, but they have been competing with Houthi rebels and